At this time of year, the Severn River, an arm of the Chesapeake Bay that joins the latter at Annapolis, is still cold.

But on one morning this week, its Annapolis shoreside was filled with a thrashing horde of humanity previously unknown to marine researchers.

To know what happened, we have to go back a year or so. The U.S. Naval Academy formerly had a reflecting pool. For years, for reasons best left to naval mythology, graduating officers plunged into it in full uniform after their final color parade.

But last year the pool was filled and converted into a flower garden. So where else was a place to make fools of themselves?

The Severn River, of obvious course.

After this week's parade, some 40 to 50 first classmen dashed for the Severn. "Some were pulled out by friends," the Associated Press dispatch reported drily, "but others had to be picked up by rescue boats." And, one hopes, without much surety, they'll be billed for the cost of dispatching those boats.

"Some less adventuresome graduating seniors settled for a quick dip in two small fountains elsewhere on the academy grounds," the AP added.

Let's relax. It's hard to believe, but probably even the steely Adm. Ernest J. King, who ran the Navy in World War II, once did something like this, too. And maybe even Ensign-designate James E. Carter did it, too. Hard to believe.